Transcript for Ukraine Rebels Say Russians Fighting Side-by-Side with Them

You can. NATO says that more than 1000 Russian soldiers are currently operating in Ukraine and -- Ukrainian rebel forces commander admitting today. That Russian forces have been fighting side by side with the rebels against Ukrainian government forces for weeks right now -- -- hot spot eastern Ukraine hello everyone I'm. Your New York the leader of the main separatist group in southeastern Ukraine said that up to 4000. Russians. Including active duty soldiers on leave have been fighting against Ukrainian government forces. Ukraine says that is the reason that towns in eastern Ukraine have fallen back into rebel hands. Today the prime minister of Ukraine canceling a trip to Turkey because of what he called -- Russian invasion. And just a few hours ago -- released these satellite images showing Russian tanks and artillery already on the Ukrainian side of the border. NATO says that all the guns are pointing towards Ukraine the BBC's Richard Galvin has more on this crisis in Ukraine. About an apartment. The Ukrainian soldier warns his colleagues to be careful and -- -- -- it would. For months these government troops had been gaining ground against the separatist rebels in the east. But now suddenly that being pinned down and forced to retreat from several areas which had been -- -- control. The votes -- received -- look at -- moved to Chicago where you. Today this rebel leader on it sounds as -- pachinko. Revealed what may be the reason for this ten rounds he said the rebels had serving Russian soldiers fighting alongside them in that battle against Ukrainian army but he claims that the soldiers. Were on -- -- Russian forces like these have been massed along the border for months. But now there's increasing evidence that some troops how much he crossed into eastern Ukraine. Earlier this week these paratroopers were apparently -- 25 kilometers inside the country. Moscow says they crossed the border by mistake and it got lost. But Ukraine's leaders have no doubts that Russian troops events of the country secure -- -- Blum chief U. In the last few hours the presidents Patrick -- -- -- Announced -- canceled a visit to Turkey -- -- and instead is -- a meeting of his National Security Council to discuss the deteriorating situation in the country. Ukrainians believe the rebels in the cells on this town of nova results which had been under government control. Involved Russian troops. The towns now fallen and then next target could be a major city on the -- -- coast. The allegations the separatist rebels now have direct support from Russian troops is causing -- alarm in the international community. Some western leaders describing it as intolerable. And demanding an explanation. For most -- to kick out in BBC news. And you can keep up with the story in real time by downloading the ABC news happened starring this story for exclusive updates on the go. You've been watching international hot spot on Michelle Franzen in New York.

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